Wait, so am I one of the few that can run 4x32 at 4800 speed with stability?
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Your 4800CL32 is the fastest here anyway I think. When you say stable have you passed testmem5 etc?
Sad that he didn’t mention DDR5 ECC UDIMMs 
I believe those were RDIMMs, unfortunately - unless there was another announcement now for consumer space
You know, great question, I thought it did pass testmem5 at DDR5-4800 (I had previously used it to confirm that my 5200 and 5000 speeds were bad), running it overnight it came up with 1 error
Now at DDR5-4600 and testmem5 passes without errors.
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unfortunate that 4800 wasn’t stable but it really does look like there could be a 4600 brick wall. Mine fails TM5 after about an hour at 4800.
Even if we started getting 4800 stable by turning off the igpu or playing with more settings, I think in some conditions someone could be getting memory errors without knowing. At least we know because 4800 is barely unstable that its likely 4600 is fairly rock solid for us.
You could up your tREFI and claw back some of the performance from dropping from 4800 to 4600 I think too.
Maybe the next round of BIOS updates will have 2T command mode or some other memory related tweaks and we can try for 4800+
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New Bios with Agesa 1.0.0.4 are starting to roll out.
Its sparse on the changelog.
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tuning the Ram on AM5 is a nightmare …
i need the 128 gigs for work but i cant seem to get it anywere close to my speed expections
(Screenshot with Agesa 1.0.0.4 Bios)
Is that memory read speed consistent? Its significantly higher than mine but may be from cache
I would turn off your core optimizer while trying to tweak memory just so you are sure what causes a crash.
What memory settings have you tried and how unstable were they?
Memory speed is kind of inconsistent; Latency is consistent. Runs between 60 and 90 Gigs /second. So i guess Caching is involved.
Got a lot Better Latencys befor the update to Agesa 1.0.0.4 => ~~ 85 ns now after the update its ~~ 92 ns
=> Infinity Fabric @ 2100 and Memory @2100 1,1 Volts is the settings i have settled in after a lot of tests. Thats at least for me the most stable configuration. If i Change the Fabric to 2000 i can get it to run the memory @ 2200 (Stable) and it boots up with Memory @ 2300 but there OCCT does not like it an it Crashes after ~~ 40 - 50 Minutes; i can not get the system to boot with Memory + Fabric @ 2200; increasing the Voltage past 1,1 Voltes does nothing for me.
My next actions will be to try tightening the timings since they are not good at 36, 35, 35, 68. (Maybe there a bit of Voltage will help)
Do you want to try copy my settings but initially try 4400 or so?
I’m not saying they are particularly good or anything (majority have been automatically chosen by my motherboard) but it could be good to compare against your own and see if it helps or not.
I wouldn’t worry too much about your latency as you have a lot open in the background in your screenshot. My latency was also in high 90’s until I did a debloat of windows 11.
anything over 65GB/s is likely to be cache related I think due to the fabric speed but I don’t fully understand. But I would just say the 60s speeds you are getting sometimes is probably the true result and the higher one is when it hits cache.
I haven’t got the new BIOS yet (not available on the ASUS website)
I’d also just saying again if you are doing your stress testing with that curve optimizer set at -15 then the crashes could be from that instead of the memory so try to isolate your tests just to the memory and then reintroduce CO.
Hello guys!
I am new in this forum and I’ve decided to get in this insane adventure as well. I already have a 3950X and 5950X systems and I’ve build a brand new 7950X on an ROG CROSSHAIR X670E EXTREME. I am a 3D artist so 128GB are a must for me.
At 3600MHz the system is very stable and had no issues at all till now, I used the workstation for only 2 days but no crashes or other crazy things.
The only thing I did was to set manually the speed at 3600 (recommended by AMD if 4 DDR5 banks /128GB are used) and the rest is set to auto.
I tried 4600Mhz but my system was blocked on the Memory Test step and I had to pull out 2 RAM banks to be able to get in the BIOS and go back to 3600.
Now, I imagine that setting the ram speed at 4600 and leave all the rest on AUTO the system won’t work so well, do you suggest any other settings to put manually so at least it can start? As we can’t use any XMP or EXPO profiles the manual mode is a bit new to me. I am not still very expert on RAM OC yet.
I see some ZEN Timmings tables from you here but is it enought to insert those values or I need to do something else as well?
I know, my questions may seem a bit basic and hard to answer so no worries if you can’t help. I’ll follow you in any case to see how things will evolve.
Just to let you know another thing, I wrote to GIGABYTE and ASUS support a month ago and both of them confirmed (naturally), that if we need a 128GB configuration, the solution is to buy modules of 4800 speed and let the system downgrade them to 3600.
I am not very positive on a future radical change on this, 128GB is a lot for the memory controller so I gues is a bit normal having difficulties to go over it.
Thanks to all!
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Hi I had never really changed memory timings before this so I have a very basic understanding too but yes you can just copy settings from the Zentimings screenshots on this thread and stick with whichever one is stable for you.
I am really sure you will get higher than 3600 stable, that is the absolute guaranteed minimum speed that will run on the worst example of motherboard, ram, and cpu, so higher must be possible in 99% of the other cases.
I would first try to set your memory speed to 4000, Cl40-40-40, set your memory voltage to 1.25v and then leave everything else on auto. Run a short memory test with TestMem 5, it’s important to use test mem 5 because it will show errors incredibly quickly compared to normal memory tests. Seconds vs minutes or even minutes vs hours/days.
If you pass TM5 with those settings then move up slowly until you start getting errors then decide if you want to keep pushing for higher numbers or if you’re happy with whatever one you found to be stable.
You can save your bios configuration and if you get stuck with memory settings that don’t allow you to boot you can press the reset cmos button and be able to boot again, then reload the old bios settings and then try a different memory speed.
It saves a lot of time if you’ve already tweaked other settings in there so you don’t have to start from scratch each time. Especially if you’ve manually set the memory timings and just wanted to try 4600 instead of 4400 memory speed
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Thanks for answering and for the clarification.
During the Christmas vacation I’ll do with calm my tests and let you know.
Thanks again!
Did you try clearing cmos and install all 4 dimms and see if it will post?
Initially, when I first turned on the Workstation, all the dimms where install and everything was fine. I got in the BIOS, lowered down the speed manually at 3600 and start installing Win 11.
Once this was done and I did some tests to verify the speed of the build, I went to the BIOS again and brought the dimms speed at 4400 and all the rest was set on AUTO. This was my initial error, the build was always blocked at the memory training step for a lot of minutes, more than 20 if I remember well.
The strange thing is that clearing the CMOS didn’t help at all! Strange no?
At that point I took off 2 of the 4 dimms and everything came back to normal.
Last night I finished installing all my software, all the dimms are installed but they work for safety reasons at 3600.
I’ll do a backup of the C: drive first and then I’ll start playing a bit with the values you guys reported here, trying to find my build’s limits.
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I found some crazy cuckoo bird on the AnandTech forums who got 4 sticks of 16gb stable at 6000.
He did this using two different vendors! 2 sticks were Samsung and 2 were Hynix.
https://forums.anandtech.com/threads/zen-4-builders-thread.2605910/post-40905898
I found this interesting as AMD’s listed max memory speed is the same for 4x1R and 4x2R.
Max Memory Speed
2x1R DDR5-5200
2x2R DDR5-5200
4x1R DDR5-3600
4x2R DDR5-3600
Anyone have two different dual rank kits from different vendors lying around? 
@frzn If you can, try booting 5600 to 6000 CL 50-50-50-96 and see what happens.
Maybe we can run at these speeds but we need very loose timings.
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After setting up three different machines with 128GB same Corsair Vengeance SKU on DDR5 and AMD 7950X, I can tell you that the RAM seem to be very different in terms of stablity. One machine seems to be stable at 4600 but another fails with blue screens at 3600. If you have Gigabyte motherboard I do not recommend latest bios as it seems to have a bug for ram stability, I had to downgrade to make it work. Most important thing I’ve seen is to set SoC voltage to 1250 (seems to make pretty much any 128GB capacity work at minimum 4200 Mhz). Increasing this would let you higher frequency, if you are unstable at 3600, downgrade the bios to a earlier version, test first with first version of bios that the motherboard comes with.
Just made an account specifically for this topic, as I’m interested in building a server array of 7950X’s, all with 128GB RAM. I’m particularly interested in ECC RAM, since my workloads will be focused on data applications (different types of databases, to be more specific).
I’m curious if anyone here tried any ASUS boards with ECC UDIMMs. I was looking at Kingston, specifically this - KSM48E40BD8KM-32HM
There’s a list of 16/32G UDIMMs I found on another forum, I’ll cross post it here, just in case anyone has tried any of them and can report back.
DDR5 ECC UDIMM MEMORY PARTS:
M324R4GA3BB0-CQK (Samsung 32GB)
HMCG88MEBEA084N (Hynix 32GB) (supermicro MEM-DR532MD-EU48)
(Precision Workstation 3660XE Tower supports DDR5 nonECC & DDR5 ECC))
Dell AC027076 ( SNPP0YCGC/32G )
Dell AC027075 ( SNPG00XJC/16G )
M5CV-BGM2MC0P (Innodisk 32GB)
MTC20C2085S1EC48BA1R (Micron 32GB)
MTC10C1084S1EC48BA1R (Micron 16GB)